.strength-wrapper span {
    background: aliceblue;
    color: darkgray;
    padding: 2px 2px;
    flex: 1;                 /* equal width */
    text-align: center;      /* center text */
    margin-right: 4px;       /* small gap */
}

.strength-wrapper span:last-child {
    margin-right: 0;
}